DevOps Tools for Configuration, Networking & Infrastructure Debugging
Browser-based tools for validating configs, inspecting certificates, looking up DNS records, parsing HTTP requests, and checking cron schedules. No installs, no uploads — everything runs locally in your browser.
16 tools covering DNS, SSL/TLS, YAML, .htaccess, cron, robots.txt, cookies, MIME types, and user agents.
What DevOps Tools Help You Do
Infrastructure debugging is often slowed down by the overhead of reaching for the right CLI tool, parsing its output, or setting up a local environment just to inspect a certificate or validate a config file. The DevOps tools on this page remove that friction — they run entirely in your browser, require no installation, and accept raw input directly.
Whether you are on-call, debugging a deployment pipeline, or reviewing a configuration before a release, these tools give you immediate feedback: live DNS queries, SSL chain inspection, YAML syntax validation, cron schedule previews, and HTTP request parsing — all without leaving your browser tab.
DNS and SSL / TLS
DNS propagation checks and certificate validation are among the most common tasks during a deployment or incident. The DNS Record Validator queries Cloudflare's public DNS-over-HTTPS resolver to fetch live A, AAAA, MX, TXT, CNAME, and NS records for any domain — useful for confirming that a new record has propagated globally or that an email domain is configured correctly.
The SSL Certificate Validator fetches and inspects the full certificate chain for any hostname: subject, issuer, validity window, SANs, and cipher suite. The SSL Certificate Decoder accepts a raw PEM block and extracts the same fields — helpful for inspecting a certificate before deploying it or comparing a staged cert against production. For background on certificate types (DV, OV, EV), chains of trust, and Let's Encrypt, see the SSL/TLS Certificates guide. For a practical comparison of HTTP and HTTPS, see HTTP vs HTTPS.
Configuration Validation
Config files are a common source of deployment failures. A single indentation error in YAML, a malformed rewrite rule in .htaccess, or an off-by-one in a cron schedule can take down a service or silently break a feature. These tools validate before you deploy: the YAML Validator parses YAML 1.2 and reports errors with line numbers; the .htaccess Validator checks Apache rewrite rules and directive syntax; the Cron Expression Validator explains your schedule in plain English and shows the next five run times.
Robots.txt and sitemap files matter for how search engines index your site, and mistakes here are easy to miss in development. The Robots.txt Validator checks directive syntax, the Robots.txt Generator produces a correctly formatted file from a form, and the Sitemap Validator confirms that your sitemap is well-formed XML with valid URL entries.
HTTP Request Debugging
HTTP debugging often requires decomposing the components of a request: parsing the query string from a URL, decoding cookie header values, looking up the correct MIME type for a file extension, or pretty-printing a raw API response. The User-Agent Parser decodes browser and crawler user-agent strings into structured fields — useful when analysing logs or building conditional logic for device detection. All parsing runs client-side, so you can safely inspect production cookies, internal API responses, and real user-agent headers.
DevOps Tools
All tools run entirely in your browser. No configuration data is sent to any server.
Network & TLS
Look up live DNS records, inspect SSL/TLS certificates, and decode certificate chains directly in your browser — no dig or openssl required.
Configuration Validation
Validate YAML, .htaccess rules, cron schedules, robots.txt directives, and XML sitemaps before deploying. Catch syntax errors without spinning up a server.
HTTP & Request Debugging
Inspect and decode HTTP request components: query strings, cookies, MIME types, API responses, and user-agent strings — all parsed locally.
DevOps Guides & Comparisons
In-depth reference pages on configuration formats, deployment practices, and infrastructure trade-offs.
Guides
A practical guide to DevOps configuration and deployment — understand YAML, DNS records, SSL/TLS certificates, HTTP headers, cron schedules, and robots.txt. Includes validation workflows and common deployment mistakes.
A practical guide to SSL/TLS certificates — certificate types (DV, OV, EV), how certificate chains and trust work, how Let's Encrypt issues certificates via ACME, SANs and wildcards, and how to debug common certificate problems.
A practical guide to cron jobs and task scheduling — understand the five-field cron expression syntax, special strings, common patterns, timezone behaviour, and how cron works in Linux, GitHub Actions, Kubernetes CronJobs, and cloud schedulers.
A practical reference to HTTP request and response headers — what they are, common types, debugging workflows, and how headers affect caching, authentication, and browser security.
Comparisons
YAML supports comments, multi-line strings, and cleaner syntax for human-authored configs. JSON is stricter, universally supported, and the standard for APIs. Compare structure, tooling, validation, and failure modes.
HTTPS is HTTP over TLS — it adds encryption, server authentication, and data integrity. Learn why HTTPS is the baseline for all web traffic, what it does and does not protect, how it affects performance, and common migration mistakes.
DNS routing resolves domain names to IP addresses before a connection is made. HTTP routing directs requests to backends based on path, hostname, or headers after the connection is established. Most production systems use both together.
Understand how reverse proxies and load balancers differ in purpose, layer, and usage — with a comparison table and typical modern architecture.
Frequently Asked Questions
What is a DNS record and how do I look one up?
A DNS record maps a domain name to a resource — an IP address (A/AAAA), a mail server (MX), a text value (TXT), a name server (NS), or a canonical name alias (CNAME). The DNS Record Validator queries Cloudflare's DNS-over-HTTPS API (1.1.1.1) to fetch live records for any domain without installing dig or nslookup. Common use cases: confirming that a new DNS record has propagated, checking which MX servers handle email for a domain, or verifying that a Let's Encrypt TXT challenge record is visible.
How do I validate an SSL/TLS certificate without curl or openssl?
The SSL Certificate Validator fetches the certificate chain for any hostname and reports the subject, issuer, validity period, SANs (Subject Alternative Names), and cipher suite — all in your browser. This is useful for confirming that a certificate renewal has propagated, that a domain is covered by a wildcard SAN, or that the full chain (leaf + intermediates + root) is served correctly. The SSL Certificate Decoder accepts a raw PEM string if you want to inspect a certificate before deploying it.
How do I validate YAML syntax without running my application?
Paste your YAML into the YAML Validator. It parses the document with a full YAML 1.2 parser and reports syntax errors with line and column numbers. Valid documents are displayed as a formatted tree so you can visually confirm the structure before committing. Common YAML mistakes include incorrect indentation (spaces only — no tabs), unquoted strings containing colons or special characters, and duplicate keys.
What is a cron expression and how do I write one correctly?
A cron expression is a five-field string that defines a recurring schedule: minute (0–59), hour (0–23), day of month (1–31), month (1–12), and day of week (0–7, where 0 and 7 both mean Sunday). Common patterns: `* * * * *` (every minute), `0 9 * * MON-FRI` (9 AM on weekdays), `*/15 * * * *` (every 15 minutes). The Cron Expression Validator parses the expression, explains it in plain English, shows a field-by-field breakdown, and lists the next five scheduled run times — which removes guesswork from schedule configuration.
What does a robots.txt file control?
The robots.txt file sits at the root of your domain (e.g., example.com/robots.txt) and communicates crawling instructions to well-behaved search engine bots. It specifies which user-agents are targeted, which URL paths are allowed or disallowed, and optionally links to your XML sitemap. robots.txt does not block access — it is advisory. The Robots.txt Validator checks the syntax and logic of your file, and the Robots.txt Generator builds a valid file from a form interface without requiring you to remember the directive syntax.
How do I decode a user-agent string?
User-agent strings are sent by browsers and crawlers in HTTP request headers to identify the client. They follow a loosely standardised but historically inconsistent format. The User-Agent Parser breaks the string into its components: browser name and version, rendering engine, operating system, and device type. This is useful when analysing server logs, debugging mobile-specific issues, or configuring content negotiation rules. The Random User-Agent Generator produces realistic strings for testing server-side user-agent handling.
Is it safe to paste infrastructure configuration into an online tool?
Yes — every DevOps tool on this page processes data entirely in your browser using JavaScript. No configuration content, YAML files, .htaccess rules, or DNS queries are transmitted to or stored on any server (DNS lookups use Cloudflare's public DNS-over-HTTPS API, which does not log queries to us). You can safely paste production configuration files, internal hostnames, and SSL certificates. The tools work fully offline once the page has loaded.